1. Field of the Invention
The present invention relates the field of systems for access to services available on telephone networks, notably systems for coded access to communication services by mobile telephones.
2. Related Background
Such systems for access to telephone services provide for a check on the service subscription number and a check on the secret code of a user of the subscription, which prevents the use of the telephone service by unauthorised third parties.
FIG. 1 illustrates, for example, a system of a known type in which the mobile telephone set 1 is in radiotelephonic connection with a telephone network PN. The mobile telephone 1 generally functions with a standard anti-fraud device, for example with a plug-in subscription identification module SIM (chip card).
A first role of the known anti-fraud devices consists in causing the subscription number for the mobile telephone used to be recognised so that the communications of the telephone set are authorised. For example, the subscription identification module SIM produces an encrypted identification message which enables the network PN, notably a retransmission station 2 in the network, to recognise the subscription number of the mobile telephone used.
The mobile telephone 1 regularly sends identification messages during its functioning, on stand-by or in active mode, in order to indicate its presence in a coverage area (referred to as a cell) of a station 2. The location and identification of the mobile telephone 1 enables the network to route the communications intended for the mobile telephone or issuing from the mobile telephone, via the most suitable retransmission station 2. Identification of the subscription makes it possible to prevent fraud, since another telephone cannot send the same type of encrypted identification message and use the subscription of the mobile telephone 1.
A second role of the known anti-fraud devices consists of identifying the user by his secret code in order to prevent the use of the telephone by unauthorised third parties. The mobile telephone 1 generally has a numeric keypad enabling the user to key in a personal identification code PIN and to access the services of his own telephone set 1.
The standard anti-fraud devices provide for a definitive blocking of access to a mobile telephone 1 after a limited number of attempts to key in the personal identification code PIN, these attempts generally being limited to three in number.
More generally, services available on telephone networks provide for coded access with blocking procedures in the event of code errors or at the end of subscription to the service.
One drawback of the systems for coded access to services available on a communication network by coded access telephone is that the unblocking of the access can take place only through the transmission of an unblocking code to the user by the service provider and a procedure depending on the telephone used. Notably with the increasing number of mobile telephone users, and the complications of the personal identification codes resulting from this, erroneous attempts with personal identification codes and blocking of telephone sets are becoming more and more frequent. Unblocking mobile telephones creates an overload for the service provider and frustration for the user.
One aim of the present invention is to produce a system for coded access to services available on a telephone communication network, eliminating the aforementioned drawbacks, whilst preserving a high level of security for the anti-fraud device.
Succinctly, this aim is achieved by producing a system for unblocking access to a service available on a telephone network, the unblocking of the access being effected by telephone communication with a maintenance service, communications on the telephone of the user during the blocking being simply restricted to the maintenance service, or accessible by means of another subscription code.
One advantage of the access unblocking system according to the invention is that it allows remote unblocking of access since the telephone can still communicate with the maintenance centre when it is blocked.
According to the invention, a method of unblocking access to a service available on a telephone communication network is provided, the said access using identification steps utilising a set of identification data stored in an identification module, access being blocked in response to an event or in the absence of an event, access being unblocked by loading unblocking commands at the identification module, characterised in that it includes steps consisting in:
providing a supplementary set of identification data stored in the identification module, and
establishing communication between the telephone and a maintenance centre using the supplementary set when access is blocked, in order to enable remote unblocking of access to the service of the network.
In addition, the invention provides for another method of unblocking access to a service available on a telephone communication network, the said access using identification steps utilising a set of identification data stored in an identification module, access being blocked in response to an event or in the absence of an event, access being unblocked by loading unblocking commands at the identification module, characterised in that it includes steps consisting in:
providing a restricted communication mode, any communications from the telephone being restricted to a maintenance centre according to the said mode, and
using the restricted communication mode when access is blocked, in order to permit remote unblocking of access to the service of the network.
The invention applies particularly to unblocking of the code for access to a communication service by mobile telephone.
According to the invention, provision is made for a device for unblockable access to a service available on a telephone communication network, the device having subscription identification means making it possible to access the service of the network by telephone communication by transmitting a set of identification data, access being blocked in response to an event or in the absence of an event, characterised in that, when access is blocked, the identification means transmit a supplementary set of identification data and make it possible to access a maintenance centre by telephone communication, the telephone communications being restricted to the maintenance centre when the supplementary set of data is transmitted, in order to permit remote unblocking of access to the service of the network.
Provision is made for the maintenance centre to transmit unblocking commands at a distance and/or automatically, preferably according to a condensed command message service.
The invention also provides for a subscription identification chip card allowing unblockable access to a service available on a telephone communication network, the card having:
means of storing at least one set of identification data, characterised in that it has:
means able to establish restricted communications with a maintenance centre, and
means for loading and effecting access unblocking commands.